Ultrasonic flowmeter

Claim 1

IN AN ULTRACONIC FLOWMETER COMPRISING A CONDUIT SECTION CARRYING THE FLUID TO BE MEASURED, TRANSMITTING TRANSDUCER MEANS MOUNTED ON THE OUTSIDE OF THE CONDUIT SECTION TO DIRECT AN ULTRASONIC BEAM THROUGH THE WALLS OF THE CONDUIT SECTION INTO THE FLUID THEREIN, AND RECEIVING TRANSDUCER MEANS MOUNTED ON THE OUTSIDE OF THE CONDUIT SECTION ON THE OPPOSITE SIDE FROM THAT ON WHICH THE TRANSMITING TRANSDUCER IS MOUNTED TO RECEIVE ULTRASONIC SIGNALS TRANSMITTED FROM SAID IMPROVEMENT TRANSDUCER MEANS THROUGH SAID FLUID, THE IMPROVEMENT COMPRISING: DECOUPLING MEANS BETWEEN SAID TRANSMITTING AND RECEIVING TRANSDUCER MEANS FOR MINIMIZING COUPLING OF VIBRATION THEREBETWEEN DIRECTLY THROUGH THE CONDUIT SECTION WALLS, SAID DECOUPLING MEANS CMOPRISING A VIBRATION ABSORBENT MATERIAL SECURED TO THE CONDUIT SECTION WALLS ON BOTH SIDES OF THE TRANSMITTING TRANSDUCER MEANS IN DIRECTIONS BETWEEN THE TRANSMITTING AND RECEIVING TRANSDUCER MEANS, SAID VIBRATION ABSORBENT MATERIAL BEING COMPLETELY ON THE OUTSIDE OF THE CONDUIT SECTION WALLS WHERE CONTACT BETWEEN THE VIBRATION ABSORBED MATERIAL AND THE CONDUIT SECTION WALLS IS MADE SOLELY AT THE INNER MOST SURFACE OF THE VIBRATION ABSORBENT MATERIAL AND THE CONTINUITY OF THE CONDUIT SECTION WALLS IS NOT DISTURBED THEREBY, SAID VIBRATION ABSORBENT MATERIAL HAVING AN ACOUSTIC IMPEDANCE WHICH CLOSELY MATCHES THAT OF THE CONDUIT SECTION WALLS TO PERMIT PASSAGE OF A SUBSTANTIAL PART OF THE VIBRATION WAVES THROUGH THE INTERFACES OF THE CONDUIT SECTION WALLS AND THE ABSORBENT MATERIAL.